The use of evaporative cooling for both liquid and air has been long known. In relatively arid regions such as the southwestern portion of the United States, evaporative cooling has been practiced for conditioning air for human comfort. This has been practiced with varying degrees of success, particularly in relatively low demand systems such as for residences. In recent years, particularly because of the necessity to conserve energy, there has been an increased demand for improvement in efficiency and operating characteristics of systems of this kind.
Examples of the prior art disclosures of evaporative cooling for air and water systems are found in the following U.S. patents: Ray U.S. Pat. No. 1,990,194, Crawford U.S. Pat. No. Re. 20,469, Coey U.S. Pat. No. 2,162,158, Pennington U.S. Pat. No. 2,464,766, Berlowitz U.S. Pat. No. 2,488,116, Pennington U.S. Pat. No. 3,116,612, Zusmanovich U.S. Pat. Nos. 3,718,008, 3,808,832, and 3,905,205, Brown U.S. Pat. Nos. 3,812,686, 3,861,164 and 3,890,797, Schlom U.S. Pat. No. 4,023,949 and 4,156,351. See also "Indirect/Direct Evaporative Cooling Systems" ASHRAE Journal, May 1980, pp. 21-25, article by Neil Eskra.